The service was unveiled by Twitter and Square CEO Jack Dorsey at an event on Wednesday morning.

The launch was hosted by one of Square's first United Kingdom customers, the Soho Piano Bar.

Square went public in 2015. The service already operates in Canada, Japan, Australia as well as the United States.

The San Francisco Company has been trying to get a foothold in the UK market over the past year.

According to the company, the average British citizen carries less than 25 pounds ($31) in cash, while 70 percent of the country's shoppers prefer to pay by card.

However, Square estimates that about 50 percent of the United Kingdom's 5.4 million businesses do not yet accept card payments.

"We look forward to working alongside the millions of entrepreneurs and thriving small and medium-sized businesses across the UK, especially those who do not yet take card payments," Dorsey said during the launch.